/**
 * Copyright 2013-2020 the original author or authors from the JHipster project.
 *
 * This file is part of the JHipster project, see http://www.jhipster.tech/
 * for more information.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

const merge = require('../utils/object-utils').merge;
const { getTableNameFromEntityName } = require('../jhipster/entity-table-name-creator');

module.exports = class JDLEntity {
    constructor(args) {
        const merged = merge(defaults(), args);
        if (!merged.name) {
            throw new Error('The entity name is mandatory to create an entity.');
        }
        this.name = merged.name;
        this.tableName = merged.tableName || merged.name;
        this.fields = merged.fields;
        this.comment = merged.comment;
    }

    /**
     * Adds the fields to the entity.
     * @param {Iterable} fields - the fields to add
     */
    addFields(fields = []) {
        fields.forEach(field => this.addField(field));
    }

    addField(field) {
        if (!field) {
            throw new Error("Can't add nil field to the JDL entity.");
        }
        this.fields[field.name] = field;
    }

    forEachField(functionToApply) {
        if (!functionToApply) {
            throw new Error('A function must be passed to iterate over fields');
        }
        Object.values(this.fields).forEach(functionToApply);
    }

    toString() {
        let stringifiedEntity = '';
        if (this.comment) {
            stringifiedEntity += `/**\n${this.comment
                .split('\n')
                .map(line => ` * ${line}\n`)
                .join('')} */\n`;
        }
        stringifiedEntity += `entity ${this.name}`;
        if (this.tableName && getTableNameFromEntityName(this.name) !== getTableNameFromEntityName(this.tableName)) {
            stringifiedEntity += ` (${this.tableName})`;
        }
        if (Object.keys(this.fields).length !== 0) {
            stringifiedEntity += ` {\n${formatFieldObjects(this.fields)}\n}`;
        }
        return stringifiedEntity;
    }
};

function defaults() {
    return {
        fields: {},
        options: [],
    };
}

function formatFieldObjects(jdlFieldObjects) {
    let string = '';
    Object.keys(jdlFieldObjects).forEach(jdlField => {
        string += `${formatFieldObject(jdlFieldObjects[jdlField])}`;
    });
    string = `${string.slice(0, string.length - 1)}`;
    return string;
}

function formatFieldObject(jdlFieldObject) {
    let string = '';
    const lines = jdlFieldObject.toString().split('\n');
    for (let j = 0; j < lines.length; j++) {
        string += `  ${lines[j]}\n`;
    }
    string = `${string.slice(0, string.length - 1)}\n`;
    return string;
}
